Introduction to Scales
A scale is a collection of several pitches presented in either ascending or descending order. We will look at the major, minor, and chromatic scales, which are the most common scales in western music. You can also read about the whole-tone, octatonic, and pentatonic scales which play smaller, but important roles in western music.
Diatonic Scales: Major and Minor
The major and minor scales are used in the vast majority of western music written since the 17th century. These scales are considered diatonic, as opposed to chromatic (see below), as are melodies and harmonies that use the collection of pitches available in a major or minor scale.
Both major and minor scales use seven discrete pitch classes (named pitches) in a specific pattern of whole and half steps. To modern listeners, the major scale communicates a mood of happiness, triumph, joy, or contentment, whereas the minor scale can sound sad, sinister, and restless. The reason that these scales sound so different is surprisingly simple: the whole and half steps are in a different order.
Scale Degrees
Before we consider major and minor scales, we must establish some new terminology that is necessary for comparing them. A scale degree is a number or name unique to each note in a scale. Note names (letter names such as C and F-sharp) are different from scale degrees because a C may be the 3rd scale degree in one scale, but the 1st scale degree in another. The most important scale degrees to remember are tonic (1st [and 8th]), dominant (5th), and leading tone (7th).
Scale Degree Number: | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 (1) |
Scale Degree Name: | Tonic | Supertonic | Mediant | Subdominant | Dominant | Submediant | Leading Tone | Tonic |
Scale Degrees
C major scale with scale degree numbers and names
Since scale degrees 1 and 8 are the same note name and scale degree name, we will use 'tonic' to refer to these equally from here on. These numbers and names apply to both major and minor scales except that the 7th scale degree is a leading tone only when it is a half step away from the tonic. Otherwise the 7th scale degree is called the 'subtonic.'